Insurgent conflict has become the most prevalent form of warfare in the modern era. At the onset of conflict, an insurgent force is usually at a great disadvantage in comparison to the counterinsurgent force. Despite this, modern insurgents often win. What dynamics play into the strategy of the insurgents? How can an insurgent force best use its limited resources to increase its chances of success? This study shows that there are four best practices and two worst practices for insurgents. Beyond the dynamics of specific factors, this study also demonstrates that there are common "causal recipes" that help to explain the outcome of post World War II insurgencies. The analysis process for this thesis uses both a quantitative and qualitative method, using 21 variables to study 70 insurgency cases. Ultimately, this research demonstrates that insurgents must devote few material resources to attacking COIN forces and many material resources to influencing a population's perception. These findings are important to anyone who must understand what actions drive an insurgency toward eventual success or failure. The findings can explain past conflicts and can be applied to ongoing or future conflicts to better understand the dynamics at play.